The invention relates to catheters, and other medical devices for introduction into the body, which have inflatable portions.
Such devices have many functions in medical treatment. For example, coaxial or multi-lumen catheters are inserted and anchored in position by a balloon expanded within an organ to provide a fixed conduit for delivering or draining fluids. Examples are shown in Todd U.S. Pat. No. 3,983,879; Rusch U.S. Pat. No. 4,265,848 and ,Davis, Jr. U.S. Pat. No. 4,350,161. Single lumen, occlusion-type catheters are inserted into a flow path of the body, typically into arteries or veins during surgery, and a ballooned portion is used to block blood flow to an operating site. An example of this type catheter is shown in Fogerty et al. U.S. Pat. No. 3,467,101.
The ballooning portion of a typical catheter design is formed separately and is attached over the main catheter body, with a typical surface discontinuity or lateral protrusion at the point of attachment. These discontinuities can cause trauma to the tissue surrounding the point of insertion, and can hinder the insertion procedure. Other ballooning portions are formed by folding the balloon into the catheter, e.g. see Boretos U.S. Pat. No. 4,254,774, or by thinning the catheter wall, e.g. see De See U.S. Pat. No. 3,192,949, which involve difficulties in manufacture as well as in use.